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Sunday, October 1, 2017

Introspective

In the world’s
first, Chinese’s researches in China, have performed precise "chemical
surgery" on human embryos to remove disease.

Out of the three billion "letters" of our genetic code a
team of researchers at Sun Yat-sen University used a technique called
base editing to correct a single error.

They altered lab-made embryos to remove the disease beta-thalassemia. The embryos were not implanted.

The team says the approach may one day treat a range of
inherited diseases. This research is on the forefront of locating
inherited errors and correcting them chemically.

Base editing alters the fundamental building blocks of DNA: the four bases adenine, cytosine, guanine and thymine.

They are commonly known by their respective letters, A, C, G and T.

All the instructions for building and running the human body are encoded in combinations of those four bases.

According to the researchers the potentially
life-threatening blood disorder beta-thalassemia is caused by a change
to a single base in the genetic code - known as a point mutation. These
point mutations cause many life threatening inherited disorders.

The team in China have discovered a way to edit them back.

The researchers scanned the DNA for the error in the
disease beta-thalassemia then converted a G to an A, correcting the
genetic fault.

The team of researchers are the first to demonstrate
the feasibility of curing genetic disease in human embryos by the base
editor system.

The study opens new avenues for treating patients and
preventing babies being born with beta-thalassemia, and other inherited
diseases.

The experiments were performed in tissues taken from a
patient with the blood disorder and in human embryos made through
cloning. Their research is revolutionizing science using base editing an
advance on a form of gene-editing known as Crispr.

When the body tries to repair a genetic break, it
deactivates a set of instructions called a gene. It is also an
opportunity to insert new genetic information into the gene.

Base editing works on the DNA bases themselves to
convert one into another. The researchers describe the approach as
"chemical surgery".

The new technique is more efficient and has fewer
unwanted side-effects than Crispr. They have stated that about
two-thirds of known human genetic variants associated with disease are
point mutations. Base editing has the potential to directly correct, or
reproduce for research purposes, many pathogenic mutations.

The research group at Sun Yat-sen University in
Guangzhou hit the headlines before when they were the first to use
Crispr on human embryos.

Some Americans are critical of the Chinese researchers
and question why they did not do more animal research before jumping to
human embryos.

The critics are also using the Chinese scientific
advancements as the latest example of the rapidly growing ability of
scientists to manipulate human DNA. It provokes deep ethical and
societal debates about what is and is not acceptable in efforts to
prevent disease.

The critics are now calling for international
regulations to be put in place on how future research is conducted on
human embryos. In the meantime, there will be far more debates, covering
the ethics, and how this genetic research on the human genome should be
regulated.

In many countries, including China, mechanisms do need
to be established for regulation, and for long-term oversight on how
genetic research is being conducted on a global scale.

But I suppose only time will tell …….
Always with love from Suzhou, China
Thomas F O’Neill